Treatment of hydrocarbons



Feb. 17, 1942. A. szAYNA TREATMENT OF HYDRCARBONS Original Filed Aug, 6,1936 N lIJ NIPII .0 R. Qn.

mnentor Patented Feb. 17, 1942 TREATMENT F HYDRV'OCABBONS Antoni Szayna,Brooklyn, N. Y., assixnor to Albert Chester Travis, New York, N. Y.

Continuation of application Serial No. 94,578, August 6, 1936. Thisapplication September 23, 1938,' Serial No. 231,298

4 Claims.

f This invention relates to the processing of de rivative hydrocarbonproducts of crude pretroleum, shale oil, coal tar or natural gases andmore particularly to the treating and reforming of such of the foregoingproducts as are in their unfinished state unsuitable for use as motorfuel because of the low volatility and anti-knock value, poor color andodor, and the presence of elementary sulphur, corrosive organic sulphurcompounds, mercaptans, and gums, to thereby render such productssuitable for use as motor fuel,

This invention is best illustrated by its application to the processingof so-called pressure distillate, a derivative hydrocarbon product ofcrude petroleum, produced by the cracking of -crude petroleum, whichdistillate in its unfinished, that is, chemically untreated state isgenerally not suitable for immediate use as motor fuel. Such uniinisheddistillate is most frequently high in elementary sulphur, hydrogensulphide, mercaptans and gums, contains corrosive organic sulphurcompounds, and is of unpleasant odor and 'poor color.

It is to be understood, however, that derivative hydrocarbon productssuch as are contemplated herein are made up of hydrocarbons boilingwithin a range of from about 70 F. to about 700 F. or, in general,hydrocarbons Whose molecules have in the main not more than sixteen (16)carbon atoms per molecule. Such products will include hydrocarbonsforming light or heavy naphtha, kerosene or light gas oil fractionswhich in their unfinished state are unsuited -for use as motor fuel, notonly because of the features previously referred to, but particularlybecause of their low volatility.

The prior` art teaches that it is customary to separate the gasolinefraction from the heavier fractions of the distillate and to subjectthese heavier fractions` such as, for example, the naphtha, to a mildcracking or reforming operation productive of the lighter gasoline. Thisgasoline resulting fromv the naphtha reforming operation must then bechemically treated to eliminate corrosive sulphur and sulphur compounds,hydrogen sulphide, mercaptans and gums, improve the color and'reduce thetendency to gum formation.

This separate reforming and treating of the naphtha or heavier fractionsof the distillate to obtain an increased yield of finished, morevolatile gasoline suitable for use as motor fuel is an economicallyunsound and wasteful operation.

It is an object of this invention to perform as a substantially unitaryoperation the treating and reforming of derivative hydrocarbon productsof crude petroleum,shale oil, coal tar or natural gases to render suchproducts suitable for use as motor fuel.

It is an other object of this invention to reduce the sulphur and gumcontent and improve the color and odorl of derivative hydrocarbonproducts of crude petroleum, shale oil, coal tar or natural gases and inthe same operation by which vthe foregoing results are accomplished,effect an increase in the percentage of lower boiling hydrocarbons insuch products.

It is still another object of this invention to produce from aderivative hydrocarbon product of crude petroleum, shale oil, coal taror natural gases, a motor fuel having a higher lead response orsusceptibility than a motor fuel produced from the application to such aproduct of the separate reforming and treating processes heretoforeknown to the art.A

It is another object of this invention to effect the unitary treatingand reforming of unfinished derivative hydrocarbon products of crudepetroleum, shale oil, coal tar or natural gases, such as, for example,naphtha and/or kerosene, to produce thereby a finished motor fuel whichis stable as to color and gums, of desired volatility and octane number,of improved color, which is doctor stable in that it remains doctorsweet on heating or distillation, is free of elementary sulphur,hydrogen sulphide and mercaptans, and generally is low in sulphur andgum content.

It is a further object of this invention to provide a novel process foraccomplishing the foregoing and related results which is of great utilitsimple in operation and of proved economy.

Other and further objects of this invention will appear from thefollowing description and appended claims.

The accompanying drawing which forms part of the instant specificationand is to be read in conjunction therewith is a diagrammatic showing inelevation of one form of apparatus capable of carrying out the processof this invention.

In general, when processing pressure distillate, for example, thedistillate, preferably in admixture with small quantities of hydrogen isheated to a cracking temperature sufiicient to vaporize the distillateand initiate a mild cracking, or reforming, of its heavier hydrocarbons.The mixture of hot distillate vapors and hydrogen, together with somewater or steam if desired, is passed under pressure through beds ofspecially prepared inorganic materials in a series of insulated chambersor reaction zones where the treating and reforming of the distillatevapors is carried to its conclusion. For convenience, the mixture ofdistillate vapors, hydrogen, and Water or steam, if the latter lsemployed, will be termed, hereinafter, the reactant.

The specially prepared inorganic material, or contactor, as it will behereinafter termed, may be metallic iron, nickel, cobalt or copper, oroxides of these metals, or suitable combinations of these metals, or oftheir oxides, or of these metals and their oxides, preferably depositedon particles of inert refractory carriers such as porcelain, pumice,bauxite, silica gel or carborundum or combinations of such carriers.These carriers may be admixed with small quantities of metals such asaluminum, chromium, thorium, or magnesium or suitable mixtures thereof.

These contactors have the capacity of irreversibly absorbing the sulphurfrom sulphur compounds in the reactant, thus producing a reactant low insulphur and gum content and especially free of elementary sulphur,hydrogen sulphide and mercaptans. The foregoing contaotors do notinterfere with the mild cracking, or reforming of the reactant, but onthe contrary, at or above a cracking temperature and in the presence ofsmall quantities of hydrogen such contactors assist the crackingreaction in the formation of lighter hydrocarbons condensable to motorfuels of high quality, good color, and of low gum and sulphur content.The previously described contactors do not act as catalysts as such termis generally understood since they do not reversibly absorb sulphur..After passing a limited amount of the reactant over the contactor, thecontactor must be regenerated with hot air, ue gas, or steam, orsuitable mixtures thereof. The regenerated contactor is then activatedwith hydrogen to obtain a contactor of the desired special state ofactivity. A catalytic process as distinguished from the present processproduces a nished motor fuel contaminated with hydrogen sulphide whichmust subsequently be removed.

It is necessary that the contactor employed be in a special state ofactivity which is less than. its maximum state of hydrogenatingactivity. In general, a contactor is employed whose special state ofactivity is that which will eiect the desired desulphurization and thedesired hydrogenation of the gum forming constituents of the reactantwithout undesirable hydrogenation of its valuable aromatics.

The hot reactant first enters a reaction chamber containing relativelyleastactive contactor and then enters a reaction chamber containingcontactor in a relatively higher state of activity while one or morechambers containing exhausted contactor are cut out of the system forregeneration and activation of the contactor.

The chamber into which the reactant first enters contains partiallyexhausted contactor which will eiect the removal of the majority of themore 4easily removable sulphur and in this chamber most of the crackingor reforming will take place. The reactant issuing from the firstchamber enters a second chamber containing contactor of a higher stateof activity. This higher state of activity is preferably that whichexhibits, first, a pronounced desulphurizing action on the more dicultlyremovable sulphur compounds, and second, a relatively low hydrogenatingaction on the valuable aromatic hydrocarbons of the reactant.

It is known to those skilled in the art that nickel in a finely dividedstate has the capacity to decompose highly heated hydrocarbons intotheir elements. This capacity is counteracted in the practice of thisinvention by first, employing a contactor such as nickel in a partiallyexhausted, poisoned or impure state and second, by the presence ofhydrogen in the reactant.

Preferably, the system should include at least three reaction chambers,although it is possible to use two or only one, though in the lattercase batch operation must be practiced. When three chambers areemployed, although any greater number may be employed if desired, one iscut out for regeneration and activation of the contactor while thereactant undergoes treating and reforming in the remaining two. When theleast active contactor in one of the two chambers on stream becomes tooexhausted to accomplish the desired treatment in this stage, the ow ischanged so that the reactant is first fed into the second chambercontaining partially exhausted contactor and from there into the thirdchamber containing freshly regenerated and activated contactor.

The regeneration and activation of the contactor is carried on in situby rst steaming out the reaction chamber to remove residual liquid,slop, etc., then removing the sulphur from the contactor with hot air,iiue gas, or steam, or mixtures at the proper temperature and finallyactivating the hot regenerated contactor to the desired state ofactivity with a stream of hydrogen.

It is essential that the reactant be at a temperature such that a milddegree of cracking or reforming of the heavier hydrocarbons of thereactant takes place simultaneously with the treating action for sulphurabsorption, gum removal, color improvement and the formation of a stabledoctor sweet motor fuel.

The reactant on issuing from the final reaction chamber is subjected toabsorption and fractionation operations for the separation and recoveryof the hydrogen and for the recovery of treated motor fuel of thedesired end point, respectively. The treated motor fuel may be subjectedto an acid and caustic wash to remove nitrogen bases and phenols and tosecure the nal improvement in color if the source of the distillaterenders this necessary.

Referring now more particularly to the drawing, liquid to be processediiows through the pipe I and is charged by a pump 2 controlled by a flowcontroller diagrammatically shown at 3, serially through a pipe 4, vaporheat exchanger 5, pipe 6, liquid heat exchanger 1, pipe 8, vapor heatexchanger 9, and pipe I0 into a convection heating coil II positioned ina combustion gas passageway I2 of a tube still I3 provided with burnersI4 and having the combustion gas discharging through a duct I5. The coilII is serially connected by pipe I6 with a heating coil I1 positioned ina hotter portion of the convection gas passageway. 'I'he coil I'I isconnected by a pipe I8 with a radiantly heated coil I9 whose dischargeend is connected to a high pressure vapor transfer line and inlet header20.

'Ihe header 20 is connected by means of a plurality of branch lines 2|,23 and 25 controlled respectively by valves 22, 24 and 26 to the top ofa plurality of reaction chambers 21, 28 and 29, respectively althoughthis by way of example only since the header may be connected throughbranches (not shown) to the bottoms of the reaction chambers. Althoughbut three reaction chambers are shown and described, it is to beunderstood that this is by way of example only and others may be addedif necessary.

The reaction chambers are provided with connections permitting vapors tobe processed to pass through the chambers in series or, parallel ow asdesired.

For obtaining parallel operation, the bottoms of reaction chambers 21,28 and 29 are connected by means of the pipes 32, 34 and 36,respectively, having valves 83, 35 and 31, respectively, to a pipe, orhigh pressure outlet header 38 connecting the chambers with absorptionand fractionation apparatus, as will be more fully describedhereinafter. I

For obtaining series loperation, the bottoms of reaction chambers 21, 28and 29 are4 connected The outlet header pipe 38 is connected seriallythrough the heat exchanger 9, pipe 52, heat exchanger 53, pipe 54,condenser 55 and pipe 56 to a high pressure gas separator 58. Coolingliquid inlet and exit pipes 59 and 60, respectively. are connected tothe condenser 55.

Separator 58 is provided with a drain pipe 6| controlled by a valve 62,and with suitable baiiles 63 for obtaining separation of water fromdistillate condensate. arator 58 to a header 66 provided with a drainvalve 61. A pipe 68 is connected to the header 66 for discharging water,and is provided with a trap 69.

An absorber connected to the top of separator 50 contains a spray nozzle1|, or other suitable absorption oil injection device. A tail gasdischarge pipe 12 havingpressureycontrol valves 13 and 14 connectsabsorber 10 with a hydrogen storage tank 15. A portion of the hydrogenflowing through the pipe 12 may be diverted through a pipe 16 to acompressor (not shown) by which fresh and recycle hydrogen may be fedthrough pipe 3| controlled by valve 30 into distillate owing throughpipe 4. The pipe 12 contains a pressure responsive valve governing aflow control device controlling pressure control valve 14.

The separator 58 is serially connected by a condensate discharge pipe11, having a valve 18 controlled by liquid level control device 19,vapor heat exchanger 53 and pipe 80 to a fractionating tower 8|.

Fractionating tower 8| is provided with a drain pipe 89 controlled by ablowdown valve 80. The bottom of the fractionator is serially connectedby a pipe 9| having a pump 92, controlled by a flow control device 93,through pipe 94, heat exchanger 1, pipe 95, cooler 96, pipe 91, to alean absorption oil supply pipe 98, having a valve 99 and flow meter|00a, connected to the spray nozzle 1| of absorber 10.

The pipe 91 is also connected to a fractionator bottoms discharge pipe|00 having valve |0| controlled through line |02 by a liquid levelcontrol device |03in the fractionator 8|.

The top of the fractionator is serially connected by a vapor transferpipe |04, heat exchanger 5, pipe |05, condenser |06, having coolingliquid inlet and discharge pipes |01 and |08, respec- Pipes 64 and 65connect sepg tively, and pipe |09 to a gas separator and reuxaccumulator tank |I0.

The separator I|0 is provided with a drain pipe contrclled by a valve||2 and with suitable bales ||3. Pipes ||4 and ||5 connect the separatorwith a water header |1 having a drain valve ||6. A pipe ||8 is connectedto the header ||1 for discharging water.

The separator ||0 is serially connected by pipe ||9, pump |20, pipe |2|and reflux pipe |23 to the top of fractionator 8|. A flow control device|22 connectedV between pump |20 and pipe |2| controls the rate of pumpdischarge. The reux return pipe |23 contains a valve |24 operated by asuitable device |25 connected to respond to the temperature at the topof the fractionating tower.

The pipe |2| is also connected with a pipe |26 having a valve |21controlled by a liquid level control device |28 in the separator ||0 fordelivering the net treated distillate to storage.

The apparatus for the regeneration and activation of the contactor inthe reaction chambers 21, 28 and 29 comprises an air suction pipe |3|serially connected through a filter |32, air compressor |33 and pipe |34to any suitable air heating device |35. The heater |35 is connected by atransfer pipe |35 to a utility ring header |31 having valves |38, |39,and |4I. The header |31 is connected to the tops of the reaction chamers21, 28 and 29 by means of the pipes |42, |44 and |46, respectively,having valves |43, and |41, respectively and is connected to the bottoms`of the reaction chambers 21, 28 and 29 by means of the pipes |48, and|52, respectively, controlled by the valves |49, |5| and |53,respectively. A vent pipe |54 having a valve |55 connects the ringheader |31 with the atmosphere.

Av high pressure steam pipe |56 having a throttle valve |64 and one waycheck valve |65 is connected to transfer pipe 20 for adding steam to the.reactant in such quantities as may be deemed desirable.

The pipe |56 is connected by a branch pipe |51 having a throttle valve|58 and a flow meter |59, to the heater |35 for admixing steam with airbeing heated therein. The pipe |56 is also connected by branch pipe |6|having valve |62 to the utility ring header |31 for steaming out thereaction chambersJ and/or regenerating the contactor therein.

An emergency blow down or steaming out pipe |66 having a valve |61connects ring header |31 to a cooling coil |68 in an emergency andsteaming out cooler |69. The coil |68 discharges through a pipe |10connected thereto. The coil |68 is also connected with the pipe l0 bymeans of an emergency blow down pipe |1| having a valve |12,

The storage tank 15 containing recycle hydrogen for the activation ofthe contactor in the various chambers is connected to the utility ringheader |31 by means of a pipe |13 having a pressure control valve |14and throttle valveA |15.

The following is an example of the operation'of this invention:

A heavy naphtha from a high sulphur California crude containing about0.6% sulphur, having an octane number of about 30, and boiling fromabout 300 F. up to about 450 F. was fed to the system through the pipeand charged by the pump 2 serially through the pipe 4, heat exchanger 5,pipe 6, heat exchanger 1, pipe 8, heat exchanger 9 and pipe i0 to theconvection heating section of the tube still i3. Hydrogen in ture, orreactant, thus formed heated in convection sections and |1 and radiantheating section I9 of the tube still i3 to va temperature of about 890F., sulcient to initiate a cracking or reforming of the heavierhydrocarbons of the naphtha into lighter, more volatile gasolinehydrocarbons.

The reactant on issuing from the tube still 3 at the crackingtemperature flowed serially through the pipe 20 and pipe 2|, valve 22being open, into the reaction chamber 21 containing about three tons ofpartially exhausted nickel contactor deposited on pumice. Thetemperature of the reactant during passage through the insulated chamber21 was preferably maintained between about 890 F. and about 860 F. Thereactant on issuing from the chamber through the pipe 39, valve 40 beingopen and valves 33, |49, 41 and ,|43 in pipes 32, |48, 46 and |42,respectively, being closed, flowed from thence serially through the pipe45 and the pipe 48, valve 49 being opened, into the top of reactionchamber 28, valves |5|, 42, |45 and 24 in pipes |50, 4|, |44 and 23respectively being closed.

The reactant in the chamber 28 was preferably maintained at atemperature of from about 850 F. to 800 F. during its passage over a bedof more active contactor comprising about three tons of metallic nickeldeposited on pumice, and on issuing through the pipe 34, valve 35 beingopened, entered the vapor line 38.

The treated and reformed reactant passes serially through the pipe 38,heat exchanger 9, pipe 52, heat exchanger 53, pipe 54, condenser 55, andpipe 56 into the gas separator 58 where a separation of condensate fromuncondensed gases is eiected. The separator 58 and the absorber 10connected thereto were operated substantially at the pressure existingin the reaction chambers, namely 200 lbs. per square inch. Theuncondensed gases consisting primarily of hydrogen diluted with some gasfrom the cracking or reforming operation amounting to, roughly, about 4%by weight of the naphtha to be treated is scrubbed in the absorber withlean oil injected into the absorber through the spray nozzle 1|. Thehydrogen was discharged through the pipe 12 and valves 13 and 14 intothe storage tank 15, a portion of the hydrogen being diverted throughthe pipe 12 to pipe 16 to suitable compressors (not shown) Thecondensate collecting in the separator 58 on being freed of waterthrough the water drawoi pipe 68 passed through pipe 11 at a reducedsubstantially atmospheric pressure effected by the valve 18, through theheat exchanger 53 and through pipe 80 to the fractionating tower 8|.

Steam supplied through the pipe 82 may be superheated in the tubes 83 ofthe top still |3 and passed through the line 85, the valve 86 beingopen, into the bottom of the fractionating tower 8| through theperforated pipe 88 in such amount as may be desired to facilitate thefractionation and stripping of the bottoms. The flow of this steam maybe determined by the ow meter 81. The connection 84 may be provided ifsteam from the line 82 is desired for other purposes.

The temperature and the reflux) ratio in the tower 8| was controlled soas to permit the taking overhead of cracking gases and a treatedgasoline boiling from about 90 F. to about 400 F., which gas vapormixture passes serially through pipe |04, heat exchanger S, pipe |05,condenser |06 and pipe |09 into the gas separator and reflux tank ||0. Aportion of the treated gasoline accumulating in the tank |0 is returnedthrough the pipes ||9, |2| and |23 as reflux to the fractionating towerby the pump |20. The net treated gasoline removed from the systemthrough the pipe |26 was doctor" sweet, doctor and color stable, wasfree of elementaryl sulphur, mercaptans and hydrogen sulphide, and asulphur content of only 0.05%, was of good color and odor and the octanenumbers had been improved from the original 30 to approximately 69. Inaddition, the lead response, or susceptibility, of this gasoline wasbetter than that of gasoline produced by conventional treating andreforming processes.

The tail gas from the separator |I0 was discharged from the system atreduced pressure Athrough pipe |29 and valve |30 and water separatedfrom the gasoline drawn from the accumulator through the pipe ||8.

Hydrocarbons higher boiling than are desired in the finished gasolineare withdrawn as a liquid from the bottom of the fractionator 8| throughthe pipe 8| and after cooling discharged from the system through thepipe |80, a portion of the cooled liquid being returned, however,through the pipe 98 to the spray nozzle 1| of the absorber 10 as leanabsorption oil.

The chamber 29 contains poisoned or exhausted contactor to beregenerated and activated. Following regeneration and activation of thecontactor, the chamber 29 will be cut into the system in place ofchamber 21 and the reactant will then be passed through the reactionchamber 28 containing least active contactor and then through thereaction chamber 29 which latter will contain contactor of a higherdegree of activity. The substitution of the chamber 29 for the chamber21 and the change of the ow of the vapors through the chambers 28 and 21may be eiected by obvious manipulation of the valves shown.

In regenerating the contactor in the chamber 29, air fed to thecompressor |32 through the pipe 63| was heated in the heater |35 andthen passed through the pipe |36 into the utility ring header |31. Livesteam from pipe |56 was admixed with the air by opening the valve |58 inthe pipe |51 while additional steam was passed through the pipe |60 andbranch pipe |6| into the utility ring header |31 by opening the valve|62, valve |64 being closed. The mixture of air and steam at atemperature of about 750 F. entered the chamber 29 through the pipe |46,passed through the bed of contactor in the chamber 29 and thendischarged through the pipe |52 into the header |31 from which it wasdischarged through the pipe |54, valve |55 being open. An initialsteaming out of the reaction chamber 29 prior to regeneration wascarried out to discharge the slop in the chamber 29 into the header |31through pipe |52 and from thence through the pipe |66 in which valve |61is opened into the cooling coil |68 of the cooler |69. This cooled slopor material washed from the contactor was discharged from the coolerthrough the pipe |10. The iiuid medium used for regeneration decomposesthe nickel sulphide to nickel oxide and this regenerating material ispassed over the contactor for a period of time sucient to accoml plishthe desired result. Some sulphur is left in the contactor.

The activation of the regenerated contactor relatively high temperatureof from 500 to 800 F.

is reduced by the hydrogen to the selected state of activity. The flowof hydrogen is discontinued When this state is reached which may bedetermined either as the result of experience gained from previous runsor by laboratory tests of the activated contactor.

It is to be understood that the operating conditions herein recited areby way of example only and are not to be considered as limiting sinceobviously Various changes in the conditions of time, temperature andpressure may be made, depending upon the sulphur content of the materialbeing charged and its general characteristics necessarily determiningthe operating conditions to be employed for achieving the desired degreeof reforming or cracking of the heavier hydrocarbons and treating of thecharging stock.

The following are examples of operating factors for the practice of thisprocess: Temperature range: 750 F. to 1000o F.

Pressure: Atmospheric to 1400 lbs. per sq. in.

gage.

Amount of hydrogen: Oto 5% by weight of charging stock.

Contactor: 1% to 25% by weight of charging' stock. Water (steam) 0% to5% by weight of charging stock.

Degree of cracking: The amount of cracking gasl formed should in generalnot exceed more than 8% by weight of the charging stock. Regeneration:Air, steam, nue gas or mixtures at a temperature of from 500 to 1000 F.Activation: Hydrogen reacting with contactor at 500 F'. to 800 F.

It will be observed that the objects of this invention have beenaccomplished. There has been provided a process by which thesimultaneous treating and reforming of a derivative hydrocarbon productmay be carried out to produce a treated liquid suitable for use as motorfuel. There has been provided a process by which the volatility andoctane number and the lead susceptibility of a relatively wide boilingrange hy drocarbon fraction may be increased simultaneously with theremoval of all elementary sulphur, hydrogen sulphide and mercaptans, anda substantial decrease of the other sulphur compounds. There has beenprovided a process by which a motor fuel of suitable volatility may beproduced by the unitary treating and reforming of a hydrocarbon fractionsuch as naphtha or kerosene, which motor fuel is of improved color, islow in sulphur and gum, is non-corrosive, is doctor sweet, and is doctorstable in that it does not become sour on reheating or rerunning.

It will be observed that certain features and sub-combinations are ofutility and may be employed without reference to other features andsub-combinations. This is contemplated by and is Within the scope of thefollowing claims. It is further obvious that Various changes may be madein details Within the scope of these claims without departing from thespirit of this invention. It is, therefore, to be understood that thisinvention is not to be limited to the specific details shown anddescribed. This application is a continuation of application Serial No.94,578, led August 6, 1936.

What I claim is:

1. A process for treating hydrocarbon oils to produce therefrom motorfuel substantially free of sulfur Which comprises heating said oil to acracking temperature, passing said heated oil in vapor phase inadmixturewith l to 5% of hydrogen by Weight through a body of Contact materialcomprising a metal of the group consisting of iron, nickel, cobalt andcopper in a special state of activity wherein its hydrogenating anddesulfurizing power is less than maximum throughout said body to effectremoval of sulfur from said hydrocarbon oil by absorption of sulfur fromsaid oil in said body, discontinuing the flow of said oil vapor throughsaid body, regenerating said body by removal of sulfur therefrom,controlling said regeneration to effect retention throughout said bodyof a minor proportion of sulfur in combination with said metal andeffect regeneration of said body to said special state of activity.

2. A process in accordance with claim 1 wherein regeneration is effectedby the passage through said body of an oxygen-containing gas to effectoxidation of compounds of said metal and sulfur and removal of sulfurfrom said body in a gaseous product, the reaction of said compounds andsaid oxygen is controlled to effect retention throughout said body of aminor proportion of sulfur in combination with said metal, passage ofsaid oxygen-containing gas through said body is discontinued, andreduction of oxide reaction products in said body is effected by thepassage therethrough of a hydrogen-containing gas.

3. A process in accordance with claim 1 wherein said oil is heated to atemperature of 750 to 1000 F.

4. A process in accordance with claim 1 wherein regeneration of saidbody is effected at 500 to 1000 F.

ANTONI SZAYNA.

